Decision In Malcolm Smith Trial Expected Monday

New York State Senator Malcolm Smith leaves the Federal Courthouse in White Plains with his lawyer on May 30. KEITH BEDFORD FOR THE WALL STREET JOURNAL

A federal court judge plans to decide Monday if state Sen. Malcolm Smith and two defendants’ political corruption trial will continue.

The case could be delayed, end in a mistrial or even result in a dismissal of the bribery conspiracy indictments against Mr. Smith, former City Councilman Daniel Halloran and former Queens Republican Party official Vincent Tabone.

At issue are 9,000 conversations—secretly recorded by the Federal Bureau of Investigation and involving a government cooperating witness—that prosecutors didn’t turn over to defense attorneys. Some of the conversations are in Yiddish.

Prosecutors said the recordings have nothing to do with the case in which Mr. Smith, a Democrat, is charged with trying to bribe his way onto the GOP mayoral ballot for the 2013 election. Therefore, they weren’t required to submit them to the defense, prosecutors said.

Some legal experts said that the prosecution would have been better off turning the tapes over. Usually, the government errs on the side of flooding the defendant with information so they can avoid criticism for not turning documents over and because it is time consuming for the defense to sort through all the materials, experts said.

Failure to turn over the tapes earlier “seems like a pretty big blunder on the part of the prosecution,” said Martha Rayner, a clinical associate professor of law at Fordham University.

A mistrial is a particular risk for the prosecution now, she added.Lawyers for Messrs. Halloran and Tabone said their limited examination of the recordings found information that would have made them alter their opening statements.

The attorneys, Vinoo Varghese and Deborah Misir, asked the judge to dismiss the indictments against their clients.

“The government chose to make a deal with the devil, a guy facing 4½ centuries in prison,” Mr. Varghesesaid, referring to cooperating witness Moses Stern, who worked undercover hoping to reduce a potential sentence in an unrelated fraud case.

Mr. Smith’s attorney, Gerald Shargel, requested the judge declare a mistrial, which means the government could try the case again at a later date.

All three attorneys told Judge Kenneth Karas, in U.S. District Court in White Plains, N.Y., that if he does plan to continue the trial after a “timeout,” they would need at least a week to analyze the material.

Prosecutor Justin Anderson said this office assembled nearly a dozen Yiddish translators and will provide transcripts of approximately 28 hours of calls by Monday. That would leave 48 hours of recorded calls, in English, to listen to, he said.

Mr. Anderson suggested that the defense lawyers and their staffs could do that over the weekend and the trial could resume Monday.

Judge Karas disagreed, saying there is all sorts of “mental gymnastics” a defense attorney must go through when analyzing new information. “It’s not just like sitting around listening to Beethoven,” he said.

Yiddish is spoken by some 158,991 people in the U.S., according to figures from the Census Bureau’s American Community Survey in 2007. More than three-quarters of those speakers live in the New York metro area and Poughkeepsie, N.Y.